Lightning-arrester.



No. 897,906. PATENTED SEPT. 8, 1908. P. P. H. KNIGHT.

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PATENTED SEPT. 8, 1908.

LIGHTNING ARRESTER.

APPLIGATION FILED JUNE 28; 1907- 3 SHEETSSHEET 2.

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No. 897,906. PATENTED SEPT. 8, 1908. F. P. H. KNIGHT.

LIGHTNING ARRESTBR.

APPLICATION FILED JUNE 28, 1907.

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UNITED STATES PATENT OFFICE.

FRANK P. H. KNIGHT, OF KEOKUK, IOWA, ASSIGNOR TO ELECTRIC SERVICESUPPLIES COM- PANY, OF CAMDEN, NEW JERSEY, A CORPORATION OF NEW JERSEY.

LIGHTNING-ARRESTER.

To all whom it may concern:

Be it known that I, FRANK P. H. KNIGHT, a citizen of the United States,residing at Keokuk, in the county of Lee and State of Iowa, haveinvented new and useful Improvements in Lightning-Arresters, of whichthe following is a full, clear, concise, and exact description,reference being had to the accompanying drawing, forming a part of thisspecification.

My invention relates to improvements in protective devices such as areapplied to va rious forms of electrical apparatus for the purpose ofdisrupting arcs which may form between contacts.

Particularly applicable is my invention to lightning arresters whoseduty it is, as well known, to prevent injury to machines or otherapparatus connected to the line due to a static discharge, such aslightning. The usual way of effecting this result is by pro viding aseparate path for the discharge which it is compelled to follow. As thispath does not include the apparatus to be protected, the latter is keptbeyond reach of the destructive influence of the discharge. However, inlightning arresters eflicient for this purpose the great difficulty hasbeen experienced that the line-current tends to follow the discharge,and maintains a short-circuit to the ground by keeping up the are orarcs across the discharging electrodes of the arrester. Various schemeshave been resorted to, with more or less success to check this tendencyof the line current to follow the discharge, but I'conceived the idea ofdrawing the arc of the normal or line-current away from thedischarge-gap by a shunt path of lower resistance than saiddischarging-gap and breaking it mechanically, and without affecting thedischarge-path during the operation of the circuit-breaker.

In order that my invention may be fully understood, I will now give adetailed description of the same, reference being had to theaccompanying drawings, in which Figure 1 is a face view of one form ofmy invention Fig. 2 is a top view thereof, while Fig. 3 is a side viewof the same; and Fig. 4 is a face view of a modified form of myinvention.

Although the drawings show the different parts of the device mountedupon the insu- Specification of Letters Patent.

Application filed June 28, 1907. Serial No. 381,279.

Patented Sept. 8, 1908.

lating base or panel 1, it is tobe in'ldersto that certain of the parts(as, for instance, the circuit breaker) might ust as well be locatedupon a separate support. The insulating tube 2 is held in place bybrackets 3 and 4 which engage said tube at the upper and lower ends,respectively. Surrounding the tube and carried thereby, is anelectromagnetic coil 5 whose winding is in Fig. 1 indicateddiagrammatically for a purpose hereinafter explained. This coil, whenenergized, actuates the magnetic core or plunger 6 which is capable oflongitudinal move ment in the tube 2. The core is adapted to restnormally upon the upper end of a carbon button 7 in the bottom of thetube. In this, its normal position, the core is below the coil so as tobe drawn up by the latter upon flow of current therethrough. The upperend of the core carries a rod 8, of brass or other non-magneticconductive material, projecting through an opening in the top of thetube.

The resistance-rod 9 is secured to the base by metallic clamps orbrackets 10, 11, which, in turn, are held in place by screws or bolts 12threaded into arms or extensions 13 on the base. These arms also serveto space the resistance-rod from the surface of the base. The lower endof this rod terminates in a metal cap 14 having a hemisphericalprojection 15 which constitutes one of a series of metallicdischarge-electrodes. Separated from electrode 15 by a sufficientair-gap, is the spherical electrode 16 carried by a stand ard 17, asshown in Fig. 3. Then comes the cylindrical electrode 18, followed byanother spherical electrode 19. This precise arrangement of thedischarge-electrodes, also their number and shape, is here set forth byway of illustration only, and as not being of the essence of myinvention. This will become apparent as the specification proceeds.

\Ve come now to the electrical connections of the apparatus. One of theline terminals is connected to the binding post 20, which iselectrically connected to the metallic clamp 10 and, therefore, to theresistance-rod 9. One end of the coil 5 is connected to the lower end ofrod 9 by the conductor 21, while the other end of the coil is connectedto the rod 8 through the flexible conductor 22. A suitable binding post23 is electrically connected with the carbon button 7.Discharge-electrode 16 is in electric connection with the binding post23 by means of the conductor 24.

The operation of the device is as follows: A lightning or similardischarge on the linewire will follow the path indicated by the dottedline in Fig. 1, to wit, from binding post 20, through resistance-rod 9,across the air-gaps formed by the discharge-electrodes 15, 16, 18 and19, to the binding post 25, (which is electrically connected withelectrode 19) and finally to the ground. The static discharge takes theabove traced path in preference to a path through the coil 5, for thereason that such discharge, being oscillatory in its nature, wouldencounter too high a self inductance in attempting to pass through thewinding of the coil. The path across the air gaps is the path of leastre sistance for the discharge. Now, with the arcs established across theair-gaps, the normal or line-current follows the path indicated by thedashed line in- Fig. 1, to wit, from binding post 20 throughresistance-rod 9, conductor 21, through coil 5, conductor 22, rod 8,core 6, carbon button 7, binding post 23, conductor 24, electrode 16,across an airgap to electrode 18, across a second air-gap to electrode19 binding post 25, and thence to the ground. The coil 5, therefore,becomes energized and raises its core 6, away from the contact 7. As thecore and the contact 7 are in series with the spark-gaps betweenelectrodes 16, 1S and 19, this separation of the core from contact 7interrupts the flow of normal current to the ground and denergizes thecoil. As a consequence, the core drops to its normal position, and theinstrument is reset to repeat the operation above set forth upon thepassage of another discharge.

It will be noticed that the circuit through the coil 5 is in shunt tothe air-gap formed between electrodes 15 and 16. But, in view of thefact that the resistance of this shuntpath is considerably lower thanthe resistance between the electrodes 15 and 16, the normal currentchooses the path through the coil, and is thus drawn away from thesparkgap between electrodes 15 and 16. It will further be noticed that Iprovide a permanent path for the discharge, as clearly indicated by thedotted lines in Figs. 1 and 41. I call this discharge path permanent forthe simple reason that it remains unchanged or unaffected during theoperation of the circuitbreaker. In other words, whatever the posi tionof the movable core 6, whether in contact with the carbon button 7 orseparated therefrom as when breaking the normal arc, the discharge pathalways remains in the same condition to permit the passage of static orabnormal current to the ground.

The specific embodiment of my invention as herein described in detail,is for the sake of illustration only, and is nowise intended to place alimitation upon the scope of the invention as defined in the appendedclaims. As already stated, the exact number, or configuration, orposition of the discharge-electrodes is purely a matter of choice orskill, and may be varied to suit circumstances. Then, again, it is notnecessary that only one spark-gap be shunted by the circuit-breaker: Imay shunt two or more spark-gaps, as desired, or found expedient. Nor isit essential that a plurality of spark-gaps be arranged below theshunted one; a single spark-gap might be found to be Sllfllclllt.Furthermore, the position of the series spark-gaps may be altered inseveral ways, without affecting the operation of the device. Thus, forinstance, at least one spark-gap may be located on the upper end of there sistancerod, and still be in series with the coil 5. In some cases, Imay prefer to include in the shunt path a part of the resistance-rod 9in order to divert sufficient normal current through the coil toproperly actuate the armature. Such an arrangement is illustrated inFig. 4, where one end of the coil 5 is connected by conductor 21 withthe bracket 11 which is so situated on the resistance 9 that part of thesame is in the shunt path of the normal current. Lastly, I do not wishto limit myself to the solenoid type of circuitbreaker in shunt with anair gap or air-gaps;-

as any approved form of automatic circuitbreaker may be used with allthe advantages herein mentioned, and without departing from my inventionas set forth in the follow ing claims. I will but add that by the termautomatic circuit-breaker, as herein used, I mean a circuit-breakerdesigned to automatically open the circuit and immediately close it.

Having thus described my invention, what I claim as new and desire tosecure by Letters 1 Patent of the United States is:

1. In a lightning-arrester, the combination with an automaticcircuit-breaker adapted to open the circuit and again close the same andoperated by the normal current, of a permanent discharge-path associatedwith said circuit-breaker.

2. In a lightning-arrester, the combination with a discharge-path, of anautomatic circuit-breaker adapted to open the'circuit and again closethe same and operated by the normal current and in shunt to a portion ofsaid discharge path, whereby said dischargepath remains unaffectedduring the operation of the circuit-breaker.

3. In a lightning-arrester, the combination with an automaticcircuit-breaker adapted to open the circuit and again close the same andhaving separable contacts to disrupt the normal arc, of a permanentdischarge-path associated with said circuit-breaker.

4. The combination with a discharge-path,

of an automatic circuit-breaker in shunt to a portion of saiddischarge-path and having separable contacts to disrupt the normal arc,whereby said discharge-path remains unatfected during the operation ofthe circuitbreaker.

5. In a lightning arrester, the combination with discharge-electrodeshaving air-gaps therebetween, of a shunt-path for drawing the are of thenormal current away from one or more of said air-gaps, and means forautomatically interrupting the How of normal current in said shunt-path.

6. In a lightning arr-ester, the combination with discharge-electrodeshaving air-gaps therebetween, of an automatic circuitbreaker in shunt toone or more of said airgaps and adapted to be operated by the nor malcurrent, for interrupting the how of normal current in said shunt.

7. In a lightning arrester, the combination with a discharge-path havingair-gaps therein, of a path for the normal current in shunt to one ormore of said air-gaps and in series with the other of said air-gaps, andmeans operated by normal current for disrupting the normal arc acrosssaid last-mentioned air-gaps, said discharge-path remaining unaflectedduring the operation of said disrupting means.

8. In a lightning arrester, the combination with a discharge-path havingair-gaps therein, of a path for the normal current in shunt to one ormore of said air-gaps and in series with the other of said air-gaps, andmeans operated by normal current and included. in said path fordisrupting the normal are across said last-mentioned air-gaps saiddischarge-path remaining unafiected during the operation of saiddisrupting means.

9. In a lightning arrester, the combination with a discharge-path havingair-gaps therein, of a path for the normal current in shunt to one ormore of said air-gaps and in series with the other of said air gaps, andan automatic circuit-breaker included in said path for disrupting thenormal arc across said last-mentioned air-gaps, said discharge-pathremaining unaffected during the operation of said circuit-breaker.

10. In a lightning arr-ester, the combination with discharge electrodeshaving air gaps therebetween, of a magnet-coil in shunt to one or moreof said air-gaps, said shuntpath having a lower resistance than theair-gap shunted thereby, so as to draw the arc of the normal currentaway from said shunted airgap or air-gaps, and means actuated by saidmagnet-coil for interrupting the flow of nor mal current in saidshunt-path.

11. In a lightning arrester; the combination with a discharge-pathhaving air-gaps therein, of a path for the normal current in shunt toone or more of said gaps and in series with the other of said air-gaps,a magnet coil in said path, and means actuated by said coil fordisrupting the normal arc across said last-mentioned air-gaps, saiddischargepath remaining unaffected during the operation of saiddisrupting means.

12. In a lightning arrester, the combination with discharge-electrodeshaving airgaps therebetween, of a shunt-path for drawing the are of thenormal current away from one or more of said air-gaps, and means foropening the circuit of the normal current in the shunt path.

13. In a lightning arrester, the combination with a discharge-pathhaving air-gaps therein, of a path for the normal current in shunt toone or more of said air-gaps and in series with the other of saidair-gaps, and means for mechanically disrupting the nor mal arc acrosssaid last-mentioned air-gaps, said discharge-p ath remaining unaffectedduring the operation of said disrupting means.

14. In a lightning arrester, the combina tion with a discharge-pathhaving air-gaps therein, of a path for the normal current in shunt toone or more of said air-gaps and in series with the other of saidair-gaps, and means included in said path for mechanically disruptingthe normal arc across said lastmentioned air-gaps, said discharge-pathre maining unafl'ected during the operation of said disrupting means.

15. In a lightning arrester, the combination with a discharge-pathincluding a resistance and a plurality of discharge-electrodes havingair-gaps therebetween, of a path for the normal current in shunt to partof said resistance and to one or more of the airgaps, for drawing thearc of the normal current away from said last-mentioned air-gaps.

16. In a lightning arrester, the combination with a discharge-pathincluding a resistance and a plurality of discharge-electrodes havingair-gaps therebetween, of a path for the normal current in shunt to partof said resistance and to one or more of the air-gaps, and an automaticcircuit-breaker in said shunt path for interrupting the fiow of normalcurrent therein.

17. In a lightning arrester, the combina tion with a discharge-pathincluding a resistance and a plurality of discharge-electrodes having.air-gaps therebetween, of a path for the normal current in shunt to partof said re- .sistance and to one or more of the air-gaps,

and in series with the other of the air-gaps, and an automaticcircuit-breaker in said shunt path for disrupting the normal arc acrosssaid last-mentioned air-gaps.

18. In a lightning arrester, the combination with a discharge-pathincluding a resistance and a plurality of discharge-electrodes havingair-gaps therebetween, of a path for the normal current in shunt to partof said resistance and to one or more of the air-gaps, and in serieswith the other of the air-gaps, a

magnet-coil in said shunt, and means actuated by said coil fordisruptingthe normal arc across said last-mentioned air-gaps.

19. In a ligh tning-arrester, the combination with a discharge-pathincluding a resistance and a plurality of discharge-electrodes havingair-gaps therebetween, of a path for the normal current in shunt to oneor more of the air-gaps, and an automatic circuitbreaker in said shuntpath for interrupting the flow of normal current therein, said circuitbreaker being operated by the normal current.

20. In a lightning-arrester, the combination with a discharge-pathincluding a resistance and a plurality of discharge-electrodes havingair-gaps therebetween, of a path for the normal current in shunt to oneor more of the a1r-gaps and in series with said. resistance and theother ol' the air-gaps, and an automatic circuit-breaker in said shuntpath for interrupting the flow of normal current therein.

21. In a lightning-arrester, the combination with a discharge-pathincluding a resist- 25 ance and a plurality of discharge-electrodeshaving air-gaps therebetween, of a path for the normal current in shuntto one or more of the air-gaps and in series with said resistance andthe other of the air-gaps, a magnet-coil 30 in said shunt, and meansactuated by said coil for interrupting the flow of normal current insaid shunt path.

In witness whereof, I have hereunto subscribed my name in the presenceof two wit-

